Alarm clock



FIG. 1 is a perspective view of the design;

FIG. 2 is a front view of the design;

FIG. 3 is a back view of the design;

FIG. 4 is a left side view of the design;

FIG. 5 is a right side view of the design;

FIG. 6 is a top plan view of the design; and,

FIG. 7 is a bottom plan view of the alarm clock.

The ornamental design for an alarm clock, as shown and described.